RETRACTED: Dissimilar friction stir welding between aluminum alloy and magnesium alloy at a low rotational speed

After publication of this paper, it is brought to the attention of the Editor-in-Chief that there are serious concerns around the validity of the nano hardness data presented in the paper. The authors were given opportunity and time to respond to the concerns, but after careful review it became clear that the problem remains. For this reason, we must retract the article.